A ball screw is provided in which an outer circumferential formation is formed at a portion facing a ball circulating passage out of outer circumferential surface of a nut. The ball screw includes: a screw shaft having on its outer circumferential surface a screw groove; a nut having on its inner circumferential surface a screw groove facing the screw groove; a plurality of balls rollably loaded in a spiral ball rolling passage formed by both screw grooves; and a ball circulating passage to return the balls from a start point to an end point of the ball rolling passage for recirculation. The ball circulating passage is a concaved groove formed by concaving a groove on a part of the cylindrical inner circumferential surface of the nut by plastic working. Then, a flange is integrally provided at a portion facing the ball circulating passage and the screw groove.

A forged crankshaft (1) includes a carbon steel containing S, wherein in a portion corresponding to a machined outer circumferential surface of a shaft part such as journals (J), crank pins (P), a front part (Fr), and a flange (Fl), a ratio x/y of an area rate x of sulfide in a position (X) corresponding to a parting surface of a die for finish forging to an area rate y of sulfide in a position (Y) corresponding to a bottom of a die impression of the die for finish forging is equal to or lower than 1.5. The forged crankshaft (1) can avoid an occurrence of machined surface cracks on the journals (J) and the crank pins (P) after the outer circumferential surface is machined.

The present disclosure provides a clipping tool for clipping flash from a component e.g. a gas turbine aerofoil body. The clipping tool includes a riser having a support surface for supporting the component and a punch for gripping the component on the support surface such that the flash projects laterally from the riser and the punch. The clipping tool further comprises a tool body having a clipping aperture opening to a channel within the tool body. The channel is defined by a channel wall. The riser and the punch are translatable to shear the projecting flash from the gripped component. At least a portion of the channel wall within the tool body comprises a broaching surface having at least one projection, said projection reducing the cross sectional area of the channel to less than that of the clipping aperture.

The present disclosure provides a clipping tool for clipping flash from a component e.g. a gas turbine aerofoil body. The clipping tool includes a riser having a support surface for supporting the component and a punch for gripping the component on the support surface such that the flash projects laterally from the riser and the punch. The clipping tool further comprises a tool body having a clipping aperture opening to a channel within the tool body. The channel is defined by a channel wall. The riser and the punch are translatable to shear the projecting flash from the gripped component. At least a portion of the channel wall within the tool body comprises a broaching surface having at least one projection, said projection reducing the cross sectional area of the channel to less than that of the clipping aperture.

A system and method of making a forged part. The method may include forming a workpiece in a first die unit that may be disposed in a first press, transferring the workpiece to a tooth forming die unit that may be disposed in a second press, and forming the workpiece into the forged part by forming a set of teeth on the workpiece with the tooth forming die unit.

A forging apparatus and method is disclosed in which an extrusion punch is held between an upper press and a lower press and propelled towards a billet by a ram to form an extruded shaped component. The extrusion punch has a striking face in which a recess is formed. During the extrusion process, material from the billet enters the recess so as to lock the extrusion punch and the shaped component together. Accordingly the shaped component is not lifted up with the upper press when it is separated from the lower press and so the position of the shaped component after the forging extrusion operation is known accurately and reliably.

The top plate section of the metal stock is pressed and clamped against a punch by a pad, a portion that will be at the outside of the L shaped curve is pressed and camped against a die by a blank holder, a bender is moved, and a vertical wall portion at the inside of the L shaped curved of the metal stock sheet and the flange portion joined to the vertical wall at the inside of the L shaped curve are molded. The metal stock sheet is moved in the direction toward the blank holder while the metal stock sheet being pressed and clamped, and a vertical wall portion at the outside of the L shaped curve of the L shaped hat shaped cross-section and the flange portion joined to the vertical wall at the outside of the L shaped curve are molded.

The top plate section of the metal stock is pressed and clamped against a punch by a pad, a portion that will be at the outside of the L shaped curve is pressed and camped against a die by a blank holder, a bender is moved, and a vertical wall portion at the inside of the L shaped curved of the metal stock sheet and the flange portion joined to the vertical wall at the inside of the L shaped curve are molded. The metal stock sheet is moved in the direction toward the blank holder while the metal stock sheet being pressed and clamped, and a vertical wall portion at the outside of the L shaped curve of the L shaped hat shaped cross-section and the flange portion joined to the vertical wall at the outside of the L shaped curve are molded.

A manufacturing method provides a high-quality material for ring rolling. The manufacturing method of the material for ring rolling includes a step of heating a disk-shaped material for hot forging to a hot working temperature, a step of arranging the material for hot forging onto a lower die having a convex portion with a truncated conical shape, a step of forming a thin portion by pressing a center portion of the material for hot forging by using an upper die having a convex portion with a truncated conical shape, and a step of manufacturing a material for ring rolling by removing the thin portion wherein a center of gravity on a half section of the material for ring rolling is located so as to be closer to an outer peripheral surface of the half section than a center of the half section in a thickness direction of the half section.

A manufacturing method provides a high-quality material for ring rolling. The manufacturing method of the material for ring rolling includes a step of heating a disk-shaped material for hot forging to a hot working temperature, a step of arranging the material for hot forging onto a lower die having a convex portion with a truncated conical shape, a step of forming a thin portion by pressing a center portion of the material for hot forging by using an upper die having a convex portion with a truncated conical shape, and a step of manufacturing a material for ring rolling by removing the thin portion wherein a center of gravity on a half section of the material for ring rolling is located so as to be closer to an outer peripheral surface of the half section than a center of the half section in a thickness direction of the half section.